I have one pair of Jensen input transformer JT-11P-1. I would like to use it for balancing signal from my unbalanced preamplifer NAD C1655 (output impedance 75ohm - 10V into 600ohms) - If I understand it well, it means the output is not on consumer level, but on "Pro" level. Therefore i decided to use 1:1 transformer. I would like to install the input transformers into the steel box with my miniDSP2x8. Iam little bit confused about wiring transformer leads to miniDSP. Positive input to miniDSP is clear, but Iam confused about Negative and White and Black wire from transformer. There are triangles (signal reference) for Negative, White and Black wires connected together. I think I whould to connect it to Shield/Signal ref input of miniDSP and not use the Negative input to miniDSP. Am I rigt.
The second question is about RC network . Does it make sence to calculate different values for miniDSP input impedance?
The second question is about RC network . Does it make sence to calculate different values for miniDSP input impedance?
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.... it is not opposite: I forgot to write that from unblanced RCA output of pramp it is wired by this cable http://www.engineeringradio.us/blog/wp-content/uploads/2011/03/balun1.jpg
I thoutght that A is the right...but when you see the Jensen wiring scheme, all the wires should be connected to Signal reference of input device. I hope somebody from this forum allrady used input transofrmers and can help me.
I thoutght that A is the right...but when you see the Jensen wiring scheme, all the wires should be connected to Signal reference of input device. I hope somebody from this forum allrady used input transofrmers and can help me.
No. The NAD output IS consumer level. You "can" crank it up to 10V, but in all normal use the signal level is 1V-2V.
The miniDSP *has* the appropriate inputs, the RCA jacks. Get an RCA cord, plug, play.
The transformer may have use when the NAD and DSP are *far* apart. Even so I have run quite long lines on simple unbalanced RCA cables without any problem.
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I thing there is some missaunderstanding.. Lets first resolve consumer/pro level. Maybe I dont understand it well and you can explain to me:
NAD pramp has its own amplification (4,something). The fixed PREout1 is on 0db 10V. PREout2 has a trimer and you can go down to -12db it means 2V. Therefore I mean the PREout1 is on PRO level. Iam I right or Iam missing something?
NAD pramp has its own amplification (4,something). The fixed PREout1 is on 0db 10V. PREout2 has a trimer and you can go down to -12db it means 2V. Therefore I mean the PREout1 is on PRO level. Iam I right or Iam missing something?
Please give a link to complete specs or schematic of your particular preamp, so we know what you have.
The NAD C-165BEE preamp has specs similar to the partial specs you mention.
"75 Ω Maximum Voltage Output 10 V into 600 Ω
HD (CCIF IMD, DIM 100) 0.005 % dB (ref. 20 Hz–20kHz, 2 Vout)"
It is clearly a consumer preamp, with a volume control, so you can set the desired output level.
The NAD C-165BEE preamp has specs similar to the partial specs you mention.
"75 Ω Maximum Voltage Output 10 V into 600 Ω
HD (CCIF IMD, DIM 100) 0.005 % dB (ref. 20 Hz–20kHz, 2 Vout)"
It is clearly a consumer preamp, with a volume control, so you can set the desired output level.
Sorry, I wrote " NAD C1655" .. you are righ it is NADC165 ... If I understand it well: it is consumer level, but increased by preamp to Pro level? ... In this case I can use 1:1 transformer right? in case I want to use balanced input to my miniDSP (throw the special cable unbalanced/balanced mentioned abowe)?
I have Balanced Hypex amps. I would like to go balanced from the preamp. There are many people who can say go unbalanced from many reasons and there are many people who can say dont go balanced from many reasons. I dont want to conversate about + and -. I just want to know, if I can use 1:1 transformer ... or different. And how to wire it.. .as I asked on the start of this thread.
I would like to go with according to appnotes on Jensen websites (you have to be loged in to view the PDF) http://www.jensen-transformers.com/wp-content/uploads/2014/08/an003.pdf
I think i have to buy 1:1 in according my preamp and miniDSP specitifacions. But Iam not sure... and not sure with wiring.
I think i have to buy 1:1 in according my preamp and miniDSP specitifacions. But Iam not sure... and not sure with wiring.
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